Info on device to control high DC current

[Bullnose]

I’m looking for information to buy your build an affordable device to monitor and control 1000a DC current from an automotive battery or other sources for electroplating.

 

[James]

do you realise that 1000A will drain a large automotive battery in about 2 minutes and most would not be able to provide that sort of current in the first place.

however to answer your question, I am fairly sure that you can buy solid state relays to that sort of capacity.

 

[Bullnose]

do you realise that 1000A will drain a large automotive battery in about 2 minutes and most would not be able to provide that sort of current in the first place.

however to answer your question, I am fairly sure that you can buy solid state relays to that sort of capacity.

Thanks for the reply. I don’t need anywhere near 1000 A more like a couple hundred but wanted to be able to control it precisely. Typical battery about 900 cranking amps. I was hoping to get several hours from a battery using between 50 and 250 A for different size material.

 

[James]

A large automotive battery is in the region of 100Ah
This means in theory it can provide 100A for 1 hour or 50A for 2 hours , 25A for 4 hours Etc.

For regular change / discharge you should really only use 50 to 60% of the capacity otherwise the battery will fail quickly.

 

[Bullnose]

A large automotive battery is in the region of 100Ah
This means in theory it can provide 100A for 1 hour or 50A for 2 hours , 25A for 4 hours Etc.

For regular change / discharge you should really only use 50 to 60% of the capacity otherwise the battery will fail quickly.

Ageeed. i’m hoping the forum might provide a somewhat detailed explanation and maybe even a drawing of the components necessary to make this work.

 

[GrahamPye]

Lead acid batteries can't provide that sort of current, you should consider a Lithium one, which can also be run down to almost empty without long term damage unlike a lead acid. Also discharge times are not linear - As you draw more current the battery empties much quicker.

Have a look in any Motorhome forum and you'll see lots of discussions about sourcing lithium batteries and wiring up inverters (which have similar current requirements.) For example I have a 230Ah lithium battery which will allow me to draw 200A from it, although my inverter generally "only" draws about 120A... You're going to need multiple batteries to get to more than 200A You'll also see discussions there about "shunts" which will enable you to monitor the current.

I'm not sure how you are going to control the current though, you'd probably do better to run it straight from the mains with something like a welding transformer.